The present method refers generally to a soft tissue filler or implant, and more particularly to the injection of a reabsorbable carrier with biocompatible solid particles to correct soft tissue defects and that is applicable for the augmentation of soft tissues. The soft tissue filler is used to even out skin, tissue irregularities, and for the augmentation of human body fat and/or the substitution of human body fat lost due to illness, trauma, aging, or congenital alterations.
In the medical fields of plastic surgery, dermatology and aesthetic medicine, there is currently no injectable long lasting, large volume soft tissue substitute or filler. More particularly, there is currently no injectable large volume soft tissue substitute other than human fat. In that regard, the techniques used to harvest human fat for transfer are generally done with liposuction under a general or local anesthetic, the latter if the amount being harvested is small.
Depending upon the surgeon, the patient and other factors, such as fat harvesting methods and installation techniques, anywhere from 20 to 95 percent of transferred fat is reabsorbed. Therefore, physicians traditionally inject 30% -50% more than is initially needed in order to help make up for what the body will lose. This creates an overfilled look regardless of the site to which the fat is transferred. Because human fat is reabsorbed, an additional supply is generally refrigerated for future use, or, alternatively, the harvesting of fat has to be repeated again.
Additionally, the harvesting of human fat often leaves the harvested area looking slack, uneven and hollowed out, unless of course a major amount of liposuction is conducted for the purpose of local fat reduction. Moreover, human fat harvesting can only work if the patient has sufficient fat to harvest. However, many have none. Also, generally only a small percentage of the installed harvested fat lasts longer than 12 months.
There are several soft tissue augmentation products in the marketplace. However, most such products can only be used in small quantities because they are toxic if used in large quantities. Examples of such augmentation products include “Silskin”, “Radiesse” and “Aquamid”.
Other soft tissue augmentation products are “Restylane” and “Sculptra”. These products are too temporary to be considered for large volume installation. Besides only being applicable for use in small volumes, these products are less than satisfactory due to cost.
Currently, there is only one approved synthetic permanent soft tissue filler in the international market that can be used in large quantities. This soft tissue filler is marketed under the “BioAlcamid” name and is an injectable gel that forms an endoprosthesis. It has, however, a proven history of late adverse reactions such as excessive inflammation and infection as long as five years after implantation. It is also difficult to implant correctly since a defined number of units are necessary in order to create an endoprosthesis that will encapsulate and not be reabsorbed. It cannot be effectively added to at a later time as puncturing the encapsulation will leave the endoprosthesis vulnerable to infection and chronic inflammation.
Further, the encapsulation (endoprosthesis) for carrying the “BioAlcamid” product is approximately 2 mm thick. As a result, the capsule does not allow for blood flow to travel through it, but instead blood travels around it, making it difficult to treat when there is inflammation and or infection. Indeed, the reported late adverse rate for “BioAlcamid” is in excess of 7%. Additionally over time, as skin becomes thinner, with lost elasticity, and as soft tissue diminishes, the outline of the endoprosthesis becomes visually apparent, as does its contents.
Accordingly, it would be desirable to provide a soft tissue filler for augmentation and replacement which overcomes these disadvantages.